Certain types of broadhead arrowheads include mechanically expandable blades that are mounted and arranged to deploy outwardly to an extended position when the broadhead impacts against and proceeds to penetrate the surface of a target. When hunting, such a target is preferably the prey. A larger entry opening preferably causes greater damage and faster bleeding of the prey.
Certain mechanical broadheads have blades which are pivotally mounted at their forward ends and where the rearward ends are forced to move outward to a deployed position upon impact. In alternate arrangements, the blades are pivotally mounted at a rearward end and a forward end rotates outward and rearward to a deployed position upon impact. In still further arrangements, the blades may be slidably and pivotally movable from a retracted position to a deployed position upon impact.
Premature expansion of one or more of a broadhead's blades can pose a safety hazard, can negatively effect the flight characteristics of an arrow with such a broadhead and/or can negatively effect the efficiency of the broadhead at injuring and killing the prey. Many mechanical expandable broadheads incorporate a retaining mechanism to minimize the risk of the blades moving from a retracted position to a deployed position at an undesirable or premature time, such as during storage or during flight before impact. In some mechanical broadheads, the retaining mechanism is a retaining ring or strap around an outer edge of the blades, such as a rubber band, which is typically broken upon impact, releasing the blades, but which must be replaced after each use. In other mechanical broadheads, the retaining mechanism includes a notch or detent on an inner edge of each blade which is initially retained in place by a retaining portion such as a notch, shelf or resilient band on the body of the broadhead, yet which allows the blade to disengage and deploy upon impact. Alternate retaining mechanisms can also be employed.
Objects and attendant advantages of this invention will be readily appreciated as the same become more clearly understood by references to the following detailed description when considered in connection with the accompanying drawings in which like reference numerals designate like parts throughout the figures thereof.